johnson



(No Model.)

L. A. JOHNSON 8:; N. E. JOHNSEN.

DREDGING MACHINE.

Patented July 24, 18 83.

ATTORNEYS.

N. FEKERS PhuwLillw nphlr. Walhinglon. n. c.

UNITED STATES LARENOE JOHNSON AND NELS E.

PATENT O FICE.

JOHNSEN, OF PORTLAND, OREGON.

DREDGlNG-MACHINE.

SPECIFICATION forming part of Letters Patent No. 281,883, dated July 24,1883,

Application filed April 11, 1883. (No model.)

To all whom it may concern:

Be it known that we, LARENCE A. JOHNSON and New E. J oHNsnN, ofPortland, in the county of Multnomah and State of Oregon, have inventeda new and Improved Dredging- Machine, of which the following is a full,clear, and exact description.

The object of our invention is to provide a new and improved machine forbreaking and loosening the soil at the bottom of rivers, bays, and othershallow waters, and also for agitating the waters to such an extent thatthe loosened soil will be raised by it sufficiently to be carried off bythe current or tide.

The invention consists in a dredging-machine constructed with one ormore spurred cylinders for breaking and loosening the bed of the river,&c., and with a propeller-screw for agitating the water, and causing thesame to carry the loosened sand, mud, &e., upward, so that the same canbe carried off by the current, whichpropeller is operated by the spurredcylinder. 4

The invention also consists in parts and details and combinations of thesame, as will be fully set forth and described hereinafter.

Reference is to be had to the accompanying drawings, forming part ofthis specification, in which similar letters of reference indicatecorresponding parts in all the figures.

Figure 1 is a plan view of our improved dredging-machine. Fig. 2 is alongitudinal. sectional elevation of the same. Fig. 3 is a detailenlarged sectional view of part of the spurred cylinder. Fig. 4is alongitudinal elevation of the dredging-machine and the vehicle fortransporting it on land.

In a frame, A, one or more cylinders, B, are mounted on a shaft, 0,journaled in both sides of the frame, which cylinders A are providedwith a series of spurs, spikes, or prongs, D, projecting radially fromthe cylindrical surfaces. The spurs D can be made any desired suitableshape, but are preferably made Wedgeshaped, and are alternately arrangedwith the end edge parallel with the longitudinal axis of the cylinderand its diameters. One of the cylinders B is provided at the inner endwith a circular rack, E, engaging with a bevelpinion, F, mounted on ashaft, G, journaled in the frame A, and projecting from the rear end ofthe frame A at right angles to the 1011- gitudinal axis of the cylindersB, 011 the outer end of which shaft G a propeller-screw, H, is mounted,which is surrounded by a guard or 5 5' protecting frame, J, secured, tothe rear end of the frame A. The frame A is contracted toward the front,and on the said narrowed part one or two rollers, K, are journaled,parallel with the cylinders B, which rollers support the front end ofthe frame A. A draft rope or chain, L, is secured, by means of a clevisring or hook, to the front end of the frame A. The ends of a rope orchain, M, are secured, by means of hooks or otherwise, to the frame A,at or near the middle of the length of the same, which rope or chain Mis used to raise or lower the machine out of or into the water. If themachine is to be transported on land, it is placed on a vehicle, N,provided at its rear end with crutches or recessed frames 0, forreceiving the spiked cylinders B. \Ve have shown the machine constructedwith two spiked cylinders, B, and one shaft, G, carrying apropeller-screw, H; but, if desired, it can be constructed with threecylinders B and two shafts G, carrying propeller-screws,H; or with fourcylinders B and three shafts G, carrying propeller-screws H. Thecylinders B are to be made of iron, so that their weight can force thespurs into the bed of the river or other water.

The operation is as follows: The machine is lowered upon the bed of theriver, 820., that is to'be dredged and is pulled along the same by meansof a steamer, or by means of a windlass or analogous device on shore.The spurs break the crust 0n the bed of the river and sink into the bed,and as the cylinders B are rotated by the movements of the machine thespurs will tear up and loosen the bed of the river. When the cylinders Bare revolved, the shaft G, carrying the propeller H, is revolved, andthe propelleragitates the water to a great extent, and causes it tocarry the 5 loosened sand, mud, &c., upward, and the same is thencarried off by the current of the stream, and is deposited in deeperplaces of the stream, where the strength of the current is not as greatas at the shallow places. The machine is moved to and fro over the sameground until a sufficient quantity of the bed of the river, &c., hasbeen loosened and carried off by the current.

Having thus described our invention, what we claim as new, and desire tosecure by Letters Patent, isi

1. A dredging-machine constructed with a spurred cylinder for breakingand loosening the bed of the river, and with a propellerscrew operatedby the spurred cylinder, and adapted to agitate the water, substantiallyas herein shown and described, and for the purpose set forth.

2. In a dredging-machine, the combination, with the frame A, of thespurred cylinders B, the shaft G, carrying a prope11er-screw,H, and therollers K, substantially as herein shown and described, and for thepurpose set forth.

3. I11 a dredging-machine, the combination, with the frame A, of thespurred cylinders B, the circular rack E, on one cylinder B, the shaftG, the propeller-screw H, and the pinion F, substantially as hereinshown and described, and for the purpose set forth.

4. In a dredging-niachine, the combination,

with the frame A, of the spurred cylinders B, the roller K, thepropeller-screw H, and the rope or chain M, substantially as hereinshown and described, and for the purpose set forth.

5. In a dredging-machine, the cylinder B, provided with wedge-shapedspurs, which are alternately arranged with their outer end edgesparallel with the longitudinal axis of the cylinder, and with thetransverse section thereof,

substantially as herein shown and described,

